1968 camaro with stock speedo gauge with 700r4. Recently my speedo cable got burned by my exhaust. Ordered and replaced new cable and now I can’t seem to get it to work right. When driving it reads nothing then it jumps sometimes. Tried greaing the entire cable and still no good. I tried disconnecting the cable from the transmission and putting a power drill to test and it works. Put back in and nothing. Everything worked before I changed out the cable. Is there some kind of trick?